Juske:

        Before you begin your DIC extractions you may wish to look at Graber 
and Aharon (1991) Chemical Geology (Isotope Geoscience Sec.) Vol. 94, 137-144. 
Their technique involves using a constant-temperature (25C) reaction vessel 
while acidifying the water sample, thus allowing for measurement of both C-13 
of the CO2 and 18-O of the water.


Cheers,
Rick Socki
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